1 /* 2 * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 12 /****************************************** 13 * Includes 14 ******************************************/ 15 #include <stddef.h> /* size_t, ptrdiff_t */ 16 #include "zstd_v01.h" 17 #include "error_private.h" 18 19 20 /****************************************** 21 * Static allocation 22 ******************************************/ 23 /* You can statically allocate FSE CTable/DTable as a table of unsigned using below macro */ 24 #define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1<<maxTableLog)) 25 26 /* You can statically allocate Huff0 DTable as a table of unsigned short using below macro */ 27 #define HUF_DTABLE_SIZE_U16(maxTableLog) (1 + (1<<maxTableLog)) 28 #define HUF_CREATE_STATIC_DTABLE(DTable, maxTableLog) \ 29 unsigned short DTable[HUF_DTABLE_SIZE_U16(maxTableLog)] = { maxTableLog } 30 31 32 /****************************************** 33 * Error Management 34 ******************************************/ 35 #define FSE_LIST_ERRORS(ITEM) \ 36 ITEM(FSE_OK_NoError) ITEM(FSE_ERROR_GENERIC) \ 37 ITEM(FSE_ERROR_tableLog_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooLarge) ITEM(FSE_ERROR_maxSymbolValue_tooSmall) \ 38 ITEM(FSE_ERROR_dstSize_tooSmall) ITEM(FSE_ERROR_srcSize_wrong)\ 39 ITEM(FSE_ERROR_corruptionDetected) \ 40 ITEM(FSE_ERROR_maxCode) 41 42 #define FSE_GENERATE_ENUM(ENUM) ENUM, 43 typedef enum { FSE_LIST_ERRORS(FSE_GENERATE_ENUM) } FSE_errorCodes; /* enum is exposed, to detect & handle specific errors; compare function result to -enum value */ 44 45 46 /****************************************** 47 * FSE symbol compression API 48 ******************************************/ 49 /* 50 This API consists of small unitary functions, which highly benefit from being inlined. 51 You will want to enable link-time-optimization to ensure these functions are properly inlined in your binary. 52 Visual seems to do it automatically. 53 For gcc or clang, you'll need to add -flto flag at compilation and linking stages. 54 If none of these solutions is applicable, include "fse.c" directly. 55 */ 56 57 typedef unsigned FSE_CTable; /* don't allocate that. It's just a way to be more restrictive than void* */ 58 typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ 59 60 typedef struct 61 { 62 size_t bitContainer; 63 int bitPos; 64 char* startPtr; 65 char* ptr; 66 char* endPtr; 67 } FSE_CStream_t; 68 69 typedef struct 70 { 71 ptrdiff_t value; 72 const void* stateTable; 73 const void* symbolTT; 74 unsigned stateLog; 75 } FSE_CState_t; 76 77 typedef struct 78 { 79 size_t bitContainer; 80 unsigned bitsConsumed; 81 const char* ptr; 82 const char* start; 83 } FSE_DStream_t; 84 85 typedef struct 86 { 87 size_t state; 88 const void* table; /* precise table may vary, depending on U16 */ 89 } FSE_DState_t; 90 91 typedef enum { FSE_DStream_unfinished = 0, 92 FSE_DStream_endOfBuffer = 1, 93 FSE_DStream_completed = 2, 94 FSE_DStream_tooFar = 3 } FSE_DStream_status; /* result of FSE_reloadDStream() */ 95 /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... ?! */ 96 97 98 /**************************************************************** 99 * Tuning parameters 100 ****************************************************************/ 101 /* MEMORY_USAGE : 102 * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) 103 * Increasing memory usage improves compression ratio 104 * Reduced memory usage can improve speed, due to cache effect 105 * Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ 106 #define FSE_MAX_MEMORY_USAGE 14 107 #define FSE_DEFAULT_MEMORY_USAGE 13 108 109 /* FSE_MAX_SYMBOL_VALUE : 110 * Maximum symbol value authorized. 111 * Required for proper stack allocation */ 112 #define FSE_MAX_SYMBOL_VALUE 255 113 114 115 /**************************************************************** 116 * template functions type & suffix 117 ****************************************************************/ 118 #define FSE_FUNCTION_TYPE BYTE 119 #define FSE_FUNCTION_EXTENSION 120 121 122 /**************************************************************** 123 * Byte symbol type 124 ****************************************************************/ 125 typedef struct 126 { 127 unsigned short newState; 128 unsigned char symbol; 129 unsigned char nbBits; 130 } FSE_decode_t; /* size == U32 */ 131 132 133 134 /**************************************************************** 135 * Compiler specifics 136 ****************************************************************/ 137 #ifdef _MSC_VER /* Visual Studio */ 138 # define FORCE_INLINE static __forceinline 139 # include <intrin.h> /* For Visual 2005 */ 140 # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ 141 # pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ 142 #else 143 # define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) 144 # if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ 145 # ifdef __GNUC__ 146 # define FORCE_INLINE static inline __attribute__((always_inline)) 147 # else 148 # define FORCE_INLINE static inline 149 # endif 150 # else 151 # define FORCE_INLINE static 152 # endif /* __STDC_VERSION__ */ 153 #endif 154 155 156 /**************************************************************** 157 * Includes 158 ****************************************************************/ 159 #include <stdlib.h> /* malloc, free, qsort */ 160 #include <string.h> /* memcpy, memset */ 161 #include <stdio.h> /* printf (debug) */ 162 163 164 #ifndef MEM_ACCESS_MODULE 165 #define MEM_ACCESS_MODULE 166 /**************************************************************** 167 * Basic Types 168 *****************************************************************/ 169 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ 170 # include <stdint.h> 171 typedef uint8_t BYTE; 172 typedef uint16_t U16; 173 typedef int16_t S16; 174 typedef uint32_t U32; 175 typedef int32_t S32; 176 typedef uint64_t U64; 177 typedef int64_t S64; 178 #else 179 typedef unsigned char BYTE; 180 typedef unsigned short U16; 181 typedef signed short S16; 182 typedef unsigned int U32; 183 typedef signed int S32; 184 typedef unsigned long long U64; 185 typedef signed long long S64; 186 #endif 187 188 #endif /* MEM_ACCESS_MODULE */ 189 190 /**************************************************************** 191 * Memory I/O 192 *****************************************************************/ 193 /* FSE_FORCE_MEMORY_ACCESS 194 * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. 195 * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. 196 * The below switch allow to select different access method for improved performance. 197 * Method 0 (default) : use `memcpy()`. Safe and portable. 198 * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). 199 * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. 200 * Method 2 : direct access. This method is portable but violate C standard. 201 * It can generate buggy code on targets generating assembly depending on alignment. 202 * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) 203 * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. 204 * Prefer these methods in priority order (0 > 1 > 2) 205 */ 206 #ifndef FSE_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */ 207 # if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) 208 # define FSE_FORCE_MEMORY_ACCESS 2 209 # elif (defined(__INTEL_COMPILER) && !defined(WIN32)) || \ 210 (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) )) 211 # define FSE_FORCE_MEMORY_ACCESS 1 212 # endif 213 #endif 214 215 216 static unsigned FSE_32bits(void) 217 { 218 return sizeof(void*)==4; 219 } 220 221 static unsigned FSE_isLittleEndian(void) 222 { 223 const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ 224 return one.c[0]; 225 } 226 227 #if defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==2) 228 229 static U16 FSE_read16(const void* memPtr) { return *(const U16*) memPtr; } 230 static U32 FSE_read32(const void* memPtr) { return *(const U32*) memPtr; } 231 static U64 FSE_read64(const void* memPtr) { return *(const U64*) memPtr; } 232 233 #elif defined(FSE_FORCE_MEMORY_ACCESS) && (FSE_FORCE_MEMORY_ACCESS==1) 234 235 /* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ 236 /* currently only defined for gcc and icc */ 237 typedef union { U16 u16; U32 u32; U64 u64; } __attribute__((packed)) unalign; 238 239 static U16 FSE_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } 240 static U32 FSE_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } 241 static U64 FSE_read64(const void* ptr) { return ((const unalign*)ptr)->u64; } 242 243 #else 244 245 static U16 FSE_read16(const void* memPtr) 246 { 247 U16 val; memcpy(&val, memPtr, sizeof(val)); return val; 248 } 249 250 static U32 FSE_read32(const void* memPtr) 251 { 252 U32 val; memcpy(&val, memPtr, sizeof(val)); return val; 253 } 254 255 static U64 FSE_read64(const void* memPtr) 256 { 257 U64 val; memcpy(&val, memPtr, sizeof(val)); return val; 258 } 259 260 #endif // FSE_FORCE_MEMORY_ACCESS 261 262 static U16 FSE_readLE16(const void* memPtr) 263 { 264 if (FSE_isLittleEndian()) 265 return FSE_read16(memPtr); 266 else 267 { 268 const BYTE* p = (const BYTE*)memPtr; 269 return (U16)(p[0] + (p[1]<<8)); 270 } 271 } 272 273 static U32 FSE_readLE32(const void* memPtr) 274 { 275 if (FSE_isLittleEndian()) 276 return FSE_read32(memPtr); 277 else 278 { 279 const BYTE* p = (const BYTE*)memPtr; 280 return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24)); 281 } 282 } 283 284 285 static U64 FSE_readLE64(const void* memPtr) 286 { 287 if (FSE_isLittleEndian()) 288 return FSE_read64(memPtr); 289 else 290 { 291 const BYTE* p = (const BYTE*)memPtr; 292 return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24) 293 + ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56)); 294 } 295 } 296 297 static size_t FSE_readLEST(const void* memPtr) 298 { 299 if (FSE_32bits()) 300 return (size_t)FSE_readLE32(memPtr); 301 else 302 return (size_t)FSE_readLE64(memPtr); 303 } 304 305 306 307 /**************************************************************** 308 * Constants 309 *****************************************************************/ 310 #define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE-2) 311 #define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG) 312 #define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1) 313 #define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2) 314 #define FSE_MIN_TABLELOG 5 315 316 #define FSE_TABLELOG_ABSOLUTE_MAX 15 317 #if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX 318 #error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported" 319 #endif 320 321 322 /**************************************************************** 323 * Error Management 324 ****************************************************************/ 325 #define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ 326 327 328 /**************************************************************** 329 * Complex types 330 ****************************************************************/ 331 typedef struct 332 { 333 int deltaFindState; 334 U32 deltaNbBits; 335 } FSE_symbolCompressionTransform; /* total 8 bytes */ 336 337 typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)]; 338 339 /**************************************************************** 340 * Internal functions 341 ****************************************************************/ 342 FORCE_INLINE unsigned FSE_highbit32 (U32 val) 343 { 344 # if defined(_MSC_VER) /* Visual */ 345 unsigned long r; 346 _BitScanReverse ( &r, val ); 347 return (unsigned) r; 348 # elif defined(__GNUC__) && (GCC_VERSION >= 304) /* GCC Intrinsic */ 349 return 31 - __builtin_clz (val); 350 # else /* Software version */ 351 static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 }; 352 U32 v = val; 353 unsigned r; 354 v |= v >> 1; 355 v |= v >> 2; 356 v |= v >> 4; 357 v |= v >> 8; 358 v |= v >> 16; 359 r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27]; 360 return r; 361 # endif 362 } 363 364 365 /**************************************************************** 366 * Templates 367 ****************************************************************/ 368 /* 369 designed to be included 370 for type-specific functions (template emulation in C) 371 Objective is to write these functions only once, for improved maintenance 372 */ 373 374 /* safety checks */ 375 #ifndef FSE_FUNCTION_EXTENSION 376 # error "FSE_FUNCTION_EXTENSION must be defined" 377 #endif 378 #ifndef FSE_FUNCTION_TYPE 379 # error "FSE_FUNCTION_TYPE must be defined" 380 #endif 381 382 /* Function names */ 383 #define FSE_CAT(X,Y) X##Y 384 #define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y) 385 #define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y) 386 387 388 389 static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; } 390 391 #define FSE_DECODE_TYPE FSE_decode_t 392 393 394 typedef struct { 395 U16 tableLog; 396 U16 fastMode; 397 } FSE_DTableHeader; /* sizeof U32 */ 398 399 static size_t FSE_buildDTable 400 (FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog) 401 { 402 void* ptr = dt; 403 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; 404 FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*)(ptr) + 1; /* because dt is unsigned, 32-bits aligned on 32-bits */ 405 const U32 tableSize = 1 << tableLog; 406 const U32 tableMask = tableSize-1; 407 const U32 step = FSE_tableStep(tableSize); 408 U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1]; 409 U32 position = 0; 410 U32 highThreshold = tableSize-1; 411 const S16 largeLimit= (S16)(1 << (tableLog-1)); 412 U32 noLarge = 1; 413 U32 s; 414 415 /* Sanity Checks */ 416 if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_maxSymbolValue_tooLarge; 417 if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_tableLog_tooLarge; 418 419 /* Init, lay down lowprob symbols */ 420 DTableH[0].tableLog = (U16)tableLog; 421 for (s=0; s<=maxSymbolValue; s++) 422 { 423 if (normalizedCounter[s]==-1) 424 { 425 tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; 426 symbolNext[s] = 1; 427 } 428 else 429 { 430 if (normalizedCounter[s] >= largeLimit) noLarge=0; 431 symbolNext[s] = normalizedCounter[s]; 432 } 433 } 434 435 /* Spread symbols */ 436 for (s=0; s<=maxSymbolValue; s++) 437 { 438 int i; 439 for (i=0; i<normalizedCounter[s]; i++) 440 { 441 tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; 442 position = (position + step) & tableMask; 443 while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */ 444 } 445 } 446 447 if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* position must reach all cells once, otherwise normalizedCounter is incorrect */ 448 449 /* Build Decoding table */ 450 { 451 U32 i; 452 for (i=0; i<tableSize; i++) 453 { 454 FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol); 455 U16 nextState = symbolNext[symbol]++; 456 tableDecode[i].nbBits = (BYTE) (tableLog - FSE_highbit32 ((U32)nextState) ); 457 tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize); 458 } 459 } 460 461 DTableH->fastMode = (U16)noLarge; 462 return 0; 463 } 464 465 466 /****************************************** 467 * FSE byte symbol 468 ******************************************/ 469 #ifndef FSE_COMMONDEFS_ONLY 470 471 static unsigned FSE_isError(size_t code) { return (code > (size_t)(-FSE_ERROR_maxCode)); } 472 473 static short FSE_abs(short a) 474 { 475 return a<0? -a : a; 476 } 477 478 479 /**************************************************************** 480 * Header bitstream management 481 ****************************************************************/ 482 static size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, 483 const void* headerBuffer, size_t hbSize) 484 { 485 const BYTE* const istart = (const BYTE*) headerBuffer; 486 const BYTE* const iend = istart + hbSize; 487 const BYTE* ip = istart; 488 int nbBits; 489 int remaining; 490 int threshold; 491 U32 bitStream; 492 int bitCount; 493 unsigned charnum = 0; 494 int previous0 = 0; 495 496 if (hbSize < 4) return (size_t)-FSE_ERROR_srcSize_wrong; 497 bitStream = FSE_readLE32(ip); 498 nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ 499 if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return (size_t)-FSE_ERROR_tableLog_tooLarge; 500 bitStream >>= 4; 501 bitCount = 4; 502 *tableLogPtr = nbBits; 503 remaining = (1<<nbBits)+1; 504 threshold = 1<<nbBits; 505 nbBits++; 506 507 while ((remaining>1) && (charnum<=*maxSVPtr)) 508 { 509 if (previous0) 510 { 511 unsigned n0 = charnum; 512 while ((bitStream & 0xFFFF) == 0xFFFF) 513 { 514 n0+=24; 515 if (ip < iend-5) 516 { 517 ip+=2; 518 bitStream = FSE_readLE32(ip) >> bitCount; 519 } 520 else 521 { 522 bitStream >>= 16; 523 bitCount+=16; 524 } 525 } 526 while ((bitStream & 3) == 3) 527 { 528 n0+=3; 529 bitStream>>=2; 530 bitCount+=2; 531 } 532 n0 += bitStream & 3; 533 bitCount += 2; 534 if (n0 > *maxSVPtr) return (size_t)-FSE_ERROR_maxSymbolValue_tooSmall; 535 while (charnum < n0) normalizedCounter[charnum++] = 0; 536 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) 537 { 538 ip += bitCount>>3; 539 bitCount &= 7; 540 bitStream = FSE_readLE32(ip) >> bitCount; 541 } 542 else 543 bitStream >>= 2; 544 } 545 { 546 const short max = (short)((2*threshold-1)-remaining); 547 short count; 548 549 if ((bitStream & (threshold-1)) < (U32)max) 550 { 551 count = (short)(bitStream & (threshold-1)); 552 bitCount += nbBits-1; 553 } 554 else 555 { 556 count = (short)(bitStream & (2*threshold-1)); 557 if (count >= threshold) count -= max; 558 bitCount += nbBits; 559 } 560 561 count--; /* extra accuracy */ 562 remaining -= FSE_abs(count); 563 normalizedCounter[charnum++] = count; 564 previous0 = !count; 565 while (remaining < threshold) 566 { 567 nbBits--; 568 threshold >>= 1; 569 } 570 571 { 572 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) 573 { 574 ip += bitCount>>3; 575 bitCount &= 7; 576 } 577 else 578 { 579 bitCount -= (int)(8 * (iend - 4 - ip)); 580 ip = iend - 4; 581 } 582 bitStream = FSE_readLE32(ip) >> (bitCount & 31); 583 } 584 } 585 } 586 if (remaining != 1) return (size_t)-FSE_ERROR_GENERIC; 587 *maxSVPtr = charnum-1; 588 589 ip += (bitCount+7)>>3; 590 if ((size_t)(ip-istart) > hbSize) return (size_t)-FSE_ERROR_srcSize_wrong; 591 return ip-istart; 592 } 593 594 595 /********************************************************* 596 * Decompression (Byte symbols) 597 *********************************************************/ 598 static size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue) 599 { 600 void* ptr = dt; 601 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; 602 FSE_decode_t* const cell = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ 603 604 DTableH->tableLog = 0; 605 DTableH->fastMode = 0; 606 607 cell->newState = 0; 608 cell->symbol = symbolValue; 609 cell->nbBits = 0; 610 611 return 0; 612 } 613 614 615 static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits) 616 { 617 void* ptr = dt; 618 FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr; 619 FSE_decode_t* const dinfo = (FSE_decode_t*)(ptr) + 1; /* because dt is unsigned */ 620 const unsigned tableSize = 1 << nbBits; 621 const unsigned tableMask = tableSize - 1; 622 const unsigned maxSymbolValue = tableMask; 623 unsigned s; 624 625 /* Sanity checks */ 626 if (nbBits < 1) return (size_t)-FSE_ERROR_GENERIC; /* min size */ 627 628 /* Build Decoding Table */ 629 DTableH->tableLog = (U16)nbBits; 630 DTableH->fastMode = 1; 631 for (s=0; s<=maxSymbolValue; s++) 632 { 633 dinfo[s].newState = 0; 634 dinfo[s].symbol = (BYTE)s; 635 dinfo[s].nbBits = (BYTE)nbBits; 636 } 637 638 return 0; 639 } 640 641 642 /* FSE_initDStream 643 * Initialize a FSE_DStream_t. 644 * srcBuffer must point at the beginning of an FSE block. 645 * The function result is the size of the FSE_block (== srcSize). 646 * If srcSize is too small, the function will return an errorCode; 647 */ 648 static size_t FSE_initDStream(FSE_DStream_t* bitD, const void* srcBuffer, size_t srcSize) 649 { 650 if (srcSize < 1) return (size_t)-FSE_ERROR_srcSize_wrong; 651 652 if (srcSize >= sizeof(size_t)) 653 { 654 U32 contain32; 655 bitD->start = (const char*)srcBuffer; 656 bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(size_t); 657 bitD->bitContainer = FSE_readLEST(bitD->ptr); 658 contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; 659 if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ 660 bitD->bitsConsumed = 8 - FSE_highbit32(contain32); 661 } 662 else 663 { 664 U32 contain32; 665 bitD->start = (const char*)srcBuffer; 666 bitD->ptr = bitD->start; 667 bitD->bitContainer = *(const BYTE*)(bitD->start); 668 switch(srcSize) 669 { 670 case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16); 671 /* fallthrough */ 672 case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24); 673 /* fallthrough */ 674 case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32); 675 /* fallthrough */ 676 case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; 677 /* fallthrough */ 678 case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; 679 /* fallthrough */ 680 case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8; 681 /* fallthrough */ 682 default:; 683 } 684 contain32 = ((const BYTE*)srcBuffer)[srcSize-1]; 685 if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */ 686 bitD->bitsConsumed = 8 - FSE_highbit32(contain32); 687 bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8; 688 } 689 690 return srcSize; 691 } 692 693 694 /*!FSE_lookBits 695 * Provides next n bits from the bitContainer. 696 * bitContainer is not modified (bits are still present for next read/look) 697 * On 32-bits, maxNbBits==25 698 * On 64-bits, maxNbBits==57 699 * return : value extracted. 700 */ 701 static size_t FSE_lookBits(FSE_DStream_t* bitD, U32 nbBits) 702 { 703 const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; 704 return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask); 705 } 706 707 static size_t FSE_lookBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ 708 { 709 const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1; 710 return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask); 711 } 712 713 static void FSE_skipBits(FSE_DStream_t* bitD, U32 nbBits) 714 { 715 bitD->bitsConsumed += nbBits; 716 } 717 718 719 /*!FSE_readBits 720 * Read next n bits from the bitContainer. 721 * On 32-bits, don't read more than maxNbBits==25 722 * On 64-bits, don't read more than maxNbBits==57 723 * Use the fast variant *only* if n >= 1. 724 * return : value extracted. 725 */ 726 static size_t FSE_readBits(FSE_DStream_t* bitD, U32 nbBits) 727 { 728 size_t value = FSE_lookBits(bitD, nbBits); 729 FSE_skipBits(bitD, nbBits); 730 return value; 731 } 732 733 static size_t FSE_readBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */ 734 { 735 size_t value = FSE_lookBitsFast(bitD, nbBits); 736 FSE_skipBits(bitD, nbBits); 737 return value; 738 } 739 740 static unsigned FSE_reloadDStream(FSE_DStream_t* bitD) 741 { 742 if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* should never happen */ 743 return FSE_DStream_tooFar; 744 745 if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) 746 { 747 bitD->ptr -= bitD->bitsConsumed >> 3; 748 bitD->bitsConsumed &= 7; 749 bitD->bitContainer = FSE_readLEST(bitD->ptr); 750 return FSE_DStream_unfinished; 751 } 752 if (bitD->ptr == bitD->start) 753 { 754 if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return FSE_DStream_endOfBuffer; 755 return FSE_DStream_completed; 756 } 757 { 758 U32 nbBytes = bitD->bitsConsumed >> 3; 759 U32 result = FSE_DStream_unfinished; 760 if (bitD->ptr - nbBytes < bitD->start) 761 { 762 nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */ 763 result = FSE_DStream_endOfBuffer; 764 } 765 bitD->ptr -= nbBytes; 766 bitD->bitsConsumed -= nbBytes*8; 767 bitD->bitContainer = FSE_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */ 768 return result; 769 } 770 } 771 772 773 static void FSE_initDState(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD, const FSE_DTable* dt) 774 { 775 const void* ptr = dt; 776 const FSE_DTableHeader* const DTableH = (const FSE_DTableHeader*)ptr; 777 DStatePtr->state = FSE_readBits(bitD, DTableH->tableLog); 778 FSE_reloadDStream(bitD); 779 DStatePtr->table = dt + 1; 780 } 781 782 static BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) 783 { 784 const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; 785 const U32 nbBits = DInfo.nbBits; 786 BYTE symbol = DInfo.symbol; 787 size_t lowBits = FSE_readBits(bitD, nbBits); 788 789 DStatePtr->state = DInfo.newState + lowBits; 790 return symbol; 791 } 792 793 static BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD) 794 { 795 const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state]; 796 const U32 nbBits = DInfo.nbBits; 797 BYTE symbol = DInfo.symbol; 798 size_t lowBits = FSE_readBitsFast(bitD, nbBits); 799 800 DStatePtr->state = DInfo.newState + lowBits; 801 return symbol; 802 } 803 804 /* FSE_endOfDStream 805 Tells if bitD has reached end of bitStream or not */ 806 807 static unsigned FSE_endOfDStream(const FSE_DStream_t* bitD) 808 { 809 return ((bitD->ptr == bitD->start) && (bitD->bitsConsumed == sizeof(bitD->bitContainer)*8)); 810 } 811 812 static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr) 813 { 814 return DStatePtr->state == 0; 815 } 816 817 818 FORCE_INLINE size_t FSE_decompress_usingDTable_generic( 819 void* dst, size_t maxDstSize, 820 const void* cSrc, size_t cSrcSize, 821 const FSE_DTable* dt, const unsigned fast) 822 { 823 BYTE* const ostart = (BYTE*) dst; 824 BYTE* op = ostart; 825 BYTE* const omax = op + maxDstSize; 826 BYTE* const olimit = omax-3; 827 828 FSE_DStream_t bitD; 829 FSE_DState_t state1; 830 FSE_DState_t state2; 831 size_t errorCode; 832 833 /* Init */ 834 errorCode = FSE_initDStream(&bitD, cSrc, cSrcSize); /* replaced last arg by maxCompressed Size */ 835 if (FSE_isError(errorCode)) return errorCode; 836 837 FSE_initDState(&state1, &bitD, dt); 838 FSE_initDState(&state2, &bitD, dt); 839 840 #define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) 841 842 /* 4 symbols per loop */ 843 for ( ; (FSE_reloadDStream(&bitD)==FSE_DStream_unfinished) && (op<olimit) ; op+=4) 844 { 845 op[0] = FSE_GETSYMBOL(&state1); 846 847 if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ 848 FSE_reloadDStream(&bitD); 849 850 op[1] = FSE_GETSYMBOL(&state2); 851 852 if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ 853 { if (FSE_reloadDStream(&bitD) > FSE_DStream_unfinished) { op+=2; break; } } 854 855 op[2] = FSE_GETSYMBOL(&state1); 856 857 if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8) /* This test must be static */ 858 FSE_reloadDStream(&bitD); 859 860 op[3] = FSE_GETSYMBOL(&state2); 861 } 862 863 /* tail */ 864 /* note : FSE_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly FSE_DStream_completed */ 865 while (1) 866 { 867 if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) ) 868 break; 869 870 *op++ = FSE_GETSYMBOL(&state1); 871 872 if ( (FSE_reloadDStream(&bitD)>FSE_DStream_completed) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) ) 873 break; 874 875 *op++ = FSE_GETSYMBOL(&state2); 876 } 877 878 /* end ? */ 879 if (FSE_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2)) 880 return op-ostart; 881 882 if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ 883 884 return (size_t)-FSE_ERROR_corruptionDetected; 885 } 886 887 888 static size_t FSE_decompress_usingDTable(void* dst, size_t originalSize, 889 const void* cSrc, size_t cSrcSize, 890 const FSE_DTable* dt) 891 { 892 FSE_DTableHeader DTableH; 893 memcpy(&DTableH, dt, sizeof(DTableH)); /* memcpy() into local variable, to avoid strict aliasing warning */ 894 895 /* select fast mode (static) */ 896 if (DTableH.fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); 897 return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); 898 } 899 900 901 static size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) 902 { 903 const BYTE* const istart = (const BYTE*)cSrc; 904 const BYTE* ip = istart; 905 short counting[FSE_MAX_SYMBOL_VALUE+1]; 906 DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */ 907 unsigned tableLog; 908 unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; 909 size_t errorCode; 910 911 if (cSrcSize<2) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ 912 913 /* normal FSE decoding mode */ 914 errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize); 915 if (FSE_isError(errorCode)) return errorCode; 916 if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */ 917 ip += errorCode; 918 cSrcSize -= errorCode; 919 920 errorCode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog); 921 if (FSE_isError(errorCode)) return errorCode; 922 923 /* always return, even if it is an error code */ 924 return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt); 925 } 926 927 928 929 /* ******************************************************* 930 * Huff0 : Huffman block compression 931 *********************************************************/ 932 #define HUF_MAX_SYMBOL_VALUE 255 933 #define HUF_DEFAULT_TABLELOG 12 /* used by default, when not specified */ 934 #define HUF_MAX_TABLELOG 12 /* max possible tableLog; for allocation purpose; can be modified */ 935 #define HUF_ABSOLUTEMAX_TABLELOG 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ 936 #if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG) 937 # error "HUF_MAX_TABLELOG is too large !" 938 #endif 939 940 typedef struct HUF_CElt_s { 941 U16 val; 942 BYTE nbBits; 943 } HUF_CElt ; 944 945 typedef struct nodeElt_s { 946 U32 count; 947 U16 parent; 948 BYTE byte; 949 BYTE nbBits; 950 } nodeElt; 951 952 953 /* ******************************************************* 954 * Huff0 : Huffman block decompression 955 *********************************************************/ 956 typedef struct { 957 BYTE byte; 958 BYTE nbBits; 959 } HUF_DElt; 960 961 static size_t HUF_readDTable (U16* DTable, const void* src, size_t srcSize) 962 { 963 BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1]; 964 U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1]; /* large enough for values from 0 to 16 */ 965 U32 weightTotal; 966 U32 maxBits; 967 const BYTE* ip = (const BYTE*) src; 968 size_t iSize; 969 size_t oSize; 970 U32 n; 971 U32 nextRankStart; 972 void* ptr = DTable+1; 973 HUF_DElt* const dt = (HUF_DElt*)ptr; 974 975 if (!srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; 976 iSize = ip[0]; 977 978 FSE_STATIC_ASSERT(sizeof(HUF_DElt) == sizeof(U16)); /* if compilation fails here, assertion is false */ 979 //memset(huffWeight, 0, sizeof(huffWeight)); /* should not be necessary, but some analyzer complain ... */ 980 if (iSize >= 128) /* special header */ 981 { 982 if (iSize >= (242)) /* RLE */ 983 { 984 static int l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 }; 985 oSize = l[iSize-242]; 986 memset(huffWeight, 1, sizeof(huffWeight)); 987 iSize = 0; 988 } 989 else /* Incompressible */ 990 { 991 oSize = iSize - 127; 992 iSize = ((oSize+1)/2); 993 if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; 994 ip += 1; 995 for (n=0; n<oSize; n+=2) 996 { 997 huffWeight[n] = ip[n/2] >> 4; 998 huffWeight[n+1] = ip[n/2] & 15; 999 } 1000 } 1001 } 1002 else /* header compressed with FSE (normal case) */ 1003 { 1004 if (iSize+1 > srcSize) return (size_t)-FSE_ERROR_srcSize_wrong; 1005 oSize = FSE_decompress(huffWeight, HUF_MAX_SYMBOL_VALUE, ip+1, iSize); /* max 255 values decoded, last one is implied */ 1006 if (FSE_isError(oSize)) return oSize; 1007 } 1008 1009 /* collect weight stats */ 1010 memset(rankVal, 0, sizeof(rankVal)); 1011 weightTotal = 0; 1012 for (n=0; n<oSize; n++) 1013 { 1014 if (huffWeight[n] >= HUF_ABSOLUTEMAX_TABLELOG) return (size_t)-FSE_ERROR_corruptionDetected; 1015 rankVal[huffWeight[n]]++; 1016 weightTotal += (1 << huffWeight[n]) >> 1; 1017 } 1018 if (weightTotal == 0) return (size_t)-FSE_ERROR_corruptionDetected; 1019 1020 /* get last non-null symbol weight (implied, total must be 2^n) */ 1021 maxBits = FSE_highbit32(weightTotal) + 1; 1022 if (maxBits > DTable[0]) return (size_t)-FSE_ERROR_tableLog_tooLarge; /* DTable is too small */ 1023 DTable[0] = (U16)maxBits; 1024 { 1025 U32 total = 1 << maxBits; 1026 U32 rest = total - weightTotal; 1027 U32 verif = 1 << FSE_highbit32(rest); 1028 U32 lastWeight = FSE_highbit32(rest) + 1; 1029 if (verif != rest) return (size_t)-FSE_ERROR_corruptionDetected; /* last value must be a clean power of 2 */ 1030 huffWeight[oSize] = (BYTE)lastWeight; 1031 rankVal[lastWeight]++; 1032 } 1033 1034 /* check tree construction validity */ 1035 if ((rankVal[1] < 2) || (rankVal[1] & 1)) return (size_t)-FSE_ERROR_corruptionDetected; /* by construction : at least 2 elts of rank 1, must be even */ 1036 1037 /* Prepare ranks */ 1038 nextRankStart = 0; 1039 for (n=1; n<=maxBits; n++) 1040 { 1041 U32 current = nextRankStart; 1042 nextRankStart += (rankVal[n] << (n-1)); 1043 rankVal[n] = current; 1044 } 1045 1046 /* fill DTable */ 1047 for (n=0; n<=oSize; n++) 1048 { 1049 const U32 w = huffWeight[n]; 1050 const U32 length = (1 << w) >> 1; 1051 U32 i; 1052 HUF_DElt D; 1053 D.byte = (BYTE)n; D.nbBits = (BYTE)(maxBits + 1 - w); 1054 for (i = rankVal[w]; i < rankVal[w] + length; i++) 1055 dt[i] = D; 1056 rankVal[w] += length; 1057 } 1058 1059 return iSize+1; 1060 } 1061 1062 1063 static BYTE HUF_decodeSymbol(FSE_DStream_t* Dstream, const HUF_DElt* dt, const U32 dtLog) 1064 { 1065 const size_t val = FSE_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ 1066 const BYTE c = dt[val].byte; 1067 FSE_skipBits(Dstream, dt[val].nbBits); 1068 return c; 1069 } 1070 1071 static size_t HUF_decompress_usingDTable( /* -3% slower when non static */ 1072 void* dst, size_t maxDstSize, 1073 const void* cSrc, size_t cSrcSize, 1074 const U16* DTable) 1075 { 1076 if (cSrcSize < 6) return (size_t)-FSE_ERROR_srcSize_wrong; 1077 { 1078 BYTE* const ostart = (BYTE*) dst; 1079 BYTE* op = ostart; 1080 BYTE* const omax = op + maxDstSize; 1081 BYTE* const olimit = omax-15; 1082 1083 const void* ptr = DTable; 1084 const HUF_DElt* const dt = (const HUF_DElt*)(ptr)+1; 1085 const U32 dtLog = DTable[0]; 1086 size_t errorCode; 1087 U32 reloadStatus; 1088 1089 /* Init */ 1090 1091 const U16* jumpTable = (const U16*)cSrc; 1092 const size_t length1 = FSE_readLE16(jumpTable); 1093 const size_t length2 = FSE_readLE16(jumpTable+1); 1094 const size_t length3 = FSE_readLE16(jumpTable+2); 1095 const size_t length4 = cSrcSize - 6 - length1 - length2 - length3; // check coherency !! 1096 const char* const start1 = (const char*)(cSrc) + 6; 1097 const char* const start2 = start1 + length1; 1098 const char* const start3 = start2 + length2; 1099 const char* const start4 = start3 + length3; 1100 FSE_DStream_t bitD1, bitD2, bitD3, bitD4; 1101 1102 if (length1+length2+length3+6 >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; 1103 1104 errorCode = FSE_initDStream(&bitD1, start1, length1); 1105 if (FSE_isError(errorCode)) return errorCode; 1106 errorCode = FSE_initDStream(&bitD2, start2, length2); 1107 if (FSE_isError(errorCode)) return errorCode; 1108 errorCode = FSE_initDStream(&bitD3, start3, length3); 1109 if (FSE_isError(errorCode)) return errorCode; 1110 errorCode = FSE_initDStream(&bitD4, start4, length4); 1111 if (FSE_isError(errorCode)) return errorCode; 1112 1113 reloadStatus=FSE_reloadDStream(&bitD2); 1114 1115 /* 16 symbols per loop */ 1116 for ( ; (reloadStatus<FSE_DStream_completed) && (op<olimit); /* D2-3-4 are supposed to be synchronized and finish together */ 1117 op+=16, reloadStatus = FSE_reloadDStream(&bitD2) | FSE_reloadDStream(&bitD3) | FSE_reloadDStream(&bitD4), FSE_reloadDStream(&bitD1)) 1118 { 1119 #define HUF_DECODE_SYMBOL_0(n, Dstream) \ 1120 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); 1121 1122 #define HUF_DECODE_SYMBOL_1(n, Dstream) \ 1123 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ 1124 if (FSE_32bits() && (HUF_MAX_TABLELOG>12)) FSE_reloadDStream(&Dstream) 1125 1126 #define HUF_DECODE_SYMBOL_2(n, Dstream) \ 1127 op[n] = HUF_decodeSymbol(&Dstream, dt, dtLog); \ 1128 if (FSE_32bits()) FSE_reloadDStream(&Dstream) 1129 1130 HUF_DECODE_SYMBOL_1( 0, bitD1); 1131 HUF_DECODE_SYMBOL_1( 1, bitD2); 1132 HUF_DECODE_SYMBOL_1( 2, bitD3); 1133 HUF_DECODE_SYMBOL_1( 3, bitD4); 1134 HUF_DECODE_SYMBOL_2( 4, bitD1); 1135 HUF_DECODE_SYMBOL_2( 5, bitD2); 1136 HUF_DECODE_SYMBOL_2( 6, bitD3); 1137 HUF_DECODE_SYMBOL_2( 7, bitD4); 1138 HUF_DECODE_SYMBOL_1( 8, bitD1); 1139 HUF_DECODE_SYMBOL_1( 9, bitD2); 1140 HUF_DECODE_SYMBOL_1(10, bitD3); 1141 HUF_DECODE_SYMBOL_1(11, bitD4); 1142 HUF_DECODE_SYMBOL_0(12, bitD1); 1143 HUF_DECODE_SYMBOL_0(13, bitD2); 1144 HUF_DECODE_SYMBOL_0(14, bitD3); 1145 HUF_DECODE_SYMBOL_0(15, bitD4); 1146 } 1147 1148 if (reloadStatus!=FSE_DStream_completed) /* not complete : some bitStream might be FSE_DStream_unfinished */ 1149 return (size_t)-FSE_ERROR_corruptionDetected; 1150 1151 /* tail */ 1152 { 1153 // bitTail = bitD1; // *much* slower : -20% !??! 1154 FSE_DStream_t bitTail; 1155 bitTail.ptr = bitD1.ptr; 1156 bitTail.bitsConsumed = bitD1.bitsConsumed; 1157 bitTail.bitContainer = bitD1.bitContainer; // required in case of FSE_DStream_endOfBuffer 1158 bitTail.start = start1; 1159 for ( ; (FSE_reloadDStream(&bitTail) < FSE_DStream_completed) && (op<omax) ; op++) 1160 { 1161 HUF_DECODE_SYMBOL_0(0, bitTail); 1162 } 1163 1164 if (FSE_endOfDStream(&bitTail)) 1165 return op-ostart; 1166 } 1167 1168 if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */ 1169 1170 return (size_t)-FSE_ERROR_corruptionDetected; 1171 } 1172 } 1173 1174 1175 static size_t HUF_decompress (void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize) 1176 { 1177 HUF_CREATE_STATIC_DTABLE(DTable, HUF_MAX_TABLELOG); 1178 const BYTE* ip = (const BYTE*) cSrc; 1179 size_t errorCode; 1180 1181 errorCode = HUF_readDTable (DTable, cSrc, cSrcSize); 1182 if (FSE_isError(errorCode)) return errorCode; 1183 if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; 1184 ip += errorCode; 1185 cSrcSize -= errorCode; 1186 1187 return HUF_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, DTable); 1188 } 1189 1190 1191 #endif /* FSE_COMMONDEFS_ONLY */ 1192 1193 /* 1194 zstd - standard compression library 1195 Copyright (C) 2014-2015, Yann Collet. 1196 1197 BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) 1198 1199 Redistribution and use in source and binary forms, with or without 1200 modification, are permitted provided that the following conditions are 1201 met: 1202 * Redistributions of source code must retain the above copyright 1203 notice, this list of conditions and the following disclaimer. 1204 * Redistributions in binary form must reproduce the above 1205 copyright notice, this list of conditions and the following disclaimer 1206 in the documentation and/or other materials provided with the 1207 distribution. 1208 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1209 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1210 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 1211 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 1212 OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 1213 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 1214 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 1215 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 1216 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 1217 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 1218 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 1219 1220 You can contact the author at : 1221 - zstd source repository : https://github.com/Cyan4973/zstd 1222 - ztsd public forum : https://groups.google.com/forum/#!forum/lz4c 1223 */ 1224 1225 /**************************************************************** 1226 * Tuning parameters 1227 *****************************************************************/ 1228 /* MEMORY_USAGE : 1229 * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) 1230 * Increasing memory usage improves compression ratio 1231 * Reduced memory usage can improve speed, due to cache effect */ 1232 #define ZSTD_MEMORY_USAGE 17 1233 1234 1235 /************************************** 1236 CPU Feature Detection 1237 **************************************/ 1238 /* 1239 * Automated efficient unaligned memory access detection 1240 * Based on known hardware architectures 1241 * This list will be updated thanks to feedbacks 1242 */ 1243 #if defined(CPU_HAS_EFFICIENT_UNALIGNED_MEMORY_ACCESS) \ 1244 || defined(__ARM_FEATURE_UNALIGNED) \ 1245 || defined(__i386__) || defined(__x86_64__) \ 1246 || defined(_M_IX86) || defined(_M_X64) \ 1247 || defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_8__) \ 1248 || (defined(_M_ARM) && (_M_ARM >= 7)) 1249 # define ZSTD_UNALIGNED_ACCESS 1 1250 #else 1251 # define ZSTD_UNALIGNED_ACCESS 0 1252 #endif 1253 1254 1255 /******************************************************** 1256 * Includes 1257 *********************************************************/ 1258 #include <stdlib.h> /* calloc */ 1259 #include <string.h> /* memcpy, memmove */ 1260 #include <stdio.h> /* debug : printf */ 1261 1262 1263 /******************************************************** 1264 * Compiler specifics 1265 *********************************************************/ 1266 #ifdef __AVX2__ 1267 # include <immintrin.h> /* AVX2 intrinsics */ 1268 #endif 1269 1270 #ifdef _MSC_VER /* Visual Studio */ 1271 # include <intrin.h> /* For Visual 2005 */ 1272 # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ 1273 # pragma warning(disable : 4324) /* disable: C4324: padded structure */ 1274 #endif 1275 1276 1277 #ifndef MEM_ACCESS_MODULE 1278 #define MEM_ACCESS_MODULE 1279 /******************************************************** 1280 * Basic Types 1281 *********************************************************/ 1282 #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ 1283 # include <stdint.h> 1284 typedef uint8_t BYTE; 1285 typedef uint16_t U16; 1286 typedef int16_t S16; 1287 typedef uint32_t U32; 1288 typedef int32_t S32; 1289 typedef uint64_t U64; 1290 #else 1291 typedef unsigned char BYTE; 1292 typedef unsigned short U16; 1293 typedef signed short S16; 1294 typedef unsigned int U32; 1295 typedef signed int S32; 1296 typedef unsigned long long U64; 1297 #endif 1298 1299 #endif /* MEM_ACCESS_MODULE */ 1300 1301 1302 /******************************************************** 1303 * Constants 1304 *********************************************************/ 1305 static const U32 ZSTD_magicNumber = 0xFD2FB51E; /* 3rd version : seqNb header */ 1306 1307 #define HASH_LOG (ZSTD_MEMORY_USAGE - 2) 1308 #define HASH_TABLESIZE (1 << HASH_LOG) 1309 #define HASH_MASK (HASH_TABLESIZE - 1) 1310 1311 #define KNUTH 2654435761 1312 1313 #define BIT7 128 1314 #define BIT6 64 1315 #define BIT5 32 1316 #define BIT4 16 1317 1318 #define KB *(1 <<10) 1319 #define MB *(1 <<20) 1320 #define GB *(1U<<30) 1321 1322 #define BLOCKSIZE (128 KB) /* define, for static allocation */ 1323 1324 #define WORKPLACESIZE (BLOCKSIZE*3) 1325 #define MINMATCH 4 1326 #define MLbits 7 1327 #define LLbits 6 1328 #define Offbits 5 1329 #define MaxML ((1<<MLbits )-1) 1330 #define MaxLL ((1<<LLbits )-1) 1331 #define MaxOff ((1<<Offbits)-1) 1332 #define LitFSELog 11 1333 #define MLFSELog 10 1334 #define LLFSELog 10 1335 #define OffFSELog 9 1336 #define MAX(a,b) ((a)<(b)?(b):(a)) 1337 #define MaxSeq MAX(MaxLL, MaxML) 1338 1339 #define LITERAL_NOENTROPY 63 1340 #define COMMAND_NOENTROPY 7 /* to remove */ 1341 1342 #define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) 1343 1344 static const size_t ZSTD_blockHeaderSize = 3; 1345 static const size_t ZSTD_frameHeaderSize = 4; 1346 1347 1348 /******************************************************** 1349 * Memory operations 1350 *********************************************************/ 1351 static unsigned ZSTD_32bits(void) { return sizeof(void*)==4; } 1352 1353 static unsigned ZSTD_isLittleEndian(void) 1354 { 1355 const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */ 1356 return one.c[0]; 1357 } 1358 1359 static U16 ZSTD_read16(const void* p) { U16 r; memcpy(&r, p, sizeof(r)); return r; } 1360 1361 static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); } 1362 1363 static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); } 1364 1365 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; } 1366 1367 static void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length) 1368 { 1369 const BYTE* ip = (const BYTE*)src; 1370 BYTE* op = (BYTE*)dst; 1371 BYTE* const oend = op + length; 1372 while (op < oend) COPY8(op, ip); 1373 } 1374 1375 static U16 ZSTD_readLE16(const void* memPtr) 1376 { 1377 if (ZSTD_isLittleEndian()) return ZSTD_read16(memPtr); 1378 else 1379 { 1380 const BYTE* p = (const BYTE*)memPtr; 1381 return (U16)((U16)p[0] + ((U16)p[1]<<8)); 1382 } 1383 } 1384 1385 static U32 ZSTD_readLE24(const void* memPtr) 1386 { 1387 return ZSTD_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16); 1388 } 1389 1390 static U32 ZSTD_readBE32(const void* memPtr) 1391 { 1392 const BYTE* p = (const BYTE*)memPtr; 1393 return (U32)(((U32)p[0]<<24) + ((U32)p[1]<<16) + ((U32)p[2]<<8) + ((U32)p[3]<<0)); 1394 } 1395 1396 1397 /************************************** 1398 * Local structures 1399 ***************************************/ 1400 typedef struct ZSTD_Cctx_s ZSTD_Cctx; 1401 1402 typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t; 1403 1404 typedef struct 1405 { 1406 blockType_t blockType; 1407 U32 origSize; 1408 } blockProperties_t; 1409 1410 typedef struct { 1411 void* buffer; 1412 U32* offsetStart; 1413 U32* offset; 1414 BYTE* offCodeStart; 1415 BYTE* offCode; 1416 BYTE* litStart; 1417 BYTE* lit; 1418 BYTE* litLengthStart; 1419 BYTE* litLength; 1420 BYTE* matchLengthStart; 1421 BYTE* matchLength; 1422 BYTE* dumpsStart; 1423 BYTE* dumps; 1424 } seqStore_t; 1425 1426 1427 typedef struct ZSTD_Cctx_s 1428 { 1429 const BYTE* base; 1430 U32 current; 1431 U32 nextUpdate; 1432 seqStore_t seqStore; 1433 #ifdef __AVX2__ 1434 __m256i hashTable[HASH_TABLESIZE>>3]; 1435 #else 1436 U32 hashTable[HASH_TABLESIZE]; 1437 #endif 1438 BYTE buffer[WORKPLACESIZE]; 1439 } cctxi_t; 1440 1441 1442 1443 1444 /************************************** 1445 * Error Management 1446 **************************************/ 1447 /* published entry point */ 1448 unsigned ZSTDv01_isError(size_t code) { return ERR_isError(code); } 1449 1450 1451 /************************************** 1452 * Tool functions 1453 **************************************/ 1454 #define ZSTD_VERSION_MAJOR 0 /* for breaking interface changes */ 1455 #define ZSTD_VERSION_MINOR 1 /* for new (non-breaking) interface capabilities */ 1456 #define ZSTD_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */ 1457 #define ZSTD_VERSION_NUMBER (ZSTD_VERSION_MAJOR *100*100 + ZSTD_VERSION_MINOR *100 + ZSTD_VERSION_RELEASE) 1458 1459 /************************************************************** 1460 * Decompression code 1461 **************************************************************/ 1462 1463 static size_t ZSTDv01_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr) 1464 { 1465 const BYTE* const in = (const BYTE* const)src; 1466 BYTE headerFlags; 1467 U32 cSize; 1468 1469 if (srcSize < 3) return ERROR(srcSize_wrong); 1470 1471 headerFlags = *in; 1472 cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16); 1473 1474 bpPtr->blockType = (blockType_t)(headerFlags >> 6); 1475 bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0; 1476 1477 if (bpPtr->blockType == bt_end) return 0; 1478 if (bpPtr->blockType == bt_rle) return 1; 1479 return cSize; 1480 } 1481 1482 1483 static size_t ZSTD_copyUncompressedBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize) 1484 { 1485 if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall); 1486 memcpy(dst, src, srcSize); 1487 return srcSize; 1488 } 1489 1490 1491 static size_t ZSTD_decompressLiterals(void* ctx, 1492 void* dst, size_t maxDstSize, 1493 const void* src, size_t srcSize) 1494 { 1495 BYTE* op = (BYTE*)dst; 1496 BYTE* const oend = op + maxDstSize; 1497 const BYTE* ip = (const BYTE*)src; 1498 size_t errorCode; 1499 size_t litSize; 1500 1501 /* check : minimum 2, for litSize, +1, for content */ 1502 if (srcSize <= 3) return ERROR(corruption_detected); 1503 1504 litSize = ip[1] + (ip[0]<<8); 1505 litSize += ((ip[-3] >> 3) & 7) << 16; // mmmmh.... 1506 op = oend - litSize; 1507 1508 (void)ctx; 1509 if (litSize > maxDstSize) return ERROR(dstSize_tooSmall); 1510 errorCode = HUF_decompress(op, litSize, ip+2, srcSize-2); 1511 if (FSE_isError(errorCode)) return ERROR(GENERIC); 1512 return litSize; 1513 } 1514 1515 1516 static size_t ZSTDv01_decodeLiteralsBlock(void* ctx, 1517 void* dst, size_t maxDstSize, 1518 const BYTE** litStart, size_t* litSize, 1519 const void* src, size_t srcSize) 1520 { 1521 const BYTE* const istart = (const BYTE* const)src; 1522 const BYTE* ip = istart; 1523 BYTE* const ostart = (BYTE* const)dst; 1524 BYTE* const oend = ostart + maxDstSize; 1525 blockProperties_t litbp; 1526 1527 size_t litcSize = ZSTDv01_getcBlockSize(src, srcSize, &litbp); 1528 if (ZSTDv01_isError(litcSize)) return litcSize; 1529 if (litcSize > srcSize - ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); 1530 ip += ZSTD_blockHeaderSize; 1531 1532 switch(litbp.blockType) 1533 { 1534 case bt_raw: 1535 *litStart = ip; 1536 ip += litcSize; 1537 *litSize = litcSize; 1538 break; 1539 case bt_rle: 1540 { 1541 size_t rleSize = litbp.origSize; 1542 if (rleSize>maxDstSize) return ERROR(dstSize_tooSmall); 1543 if (!srcSize) return ERROR(srcSize_wrong); 1544 memset(oend - rleSize, *ip, rleSize); 1545 *litStart = oend - rleSize; 1546 *litSize = rleSize; 1547 ip++; 1548 break; 1549 } 1550 case bt_compressed: 1551 { 1552 size_t decodedLitSize = ZSTD_decompressLiterals(ctx, dst, maxDstSize, ip, litcSize); 1553 if (ZSTDv01_isError(decodedLitSize)) return decodedLitSize; 1554 *litStart = oend - decodedLitSize; 1555 *litSize = decodedLitSize; 1556 ip += litcSize; 1557 break; 1558 } 1559 case bt_end: 1560 default: 1561 return ERROR(GENERIC); 1562 } 1563 1564 return ip-istart; 1565 } 1566 1567 1568 static size_t ZSTDv01_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr, 1569 FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, 1570 const void* src, size_t srcSize) 1571 { 1572 const BYTE* const istart = (const BYTE* const)src; 1573 const BYTE* ip = istart; 1574 const BYTE* const iend = istart + srcSize; 1575 U32 LLtype, Offtype, MLtype; 1576 U32 LLlog, Offlog, MLlog; 1577 size_t dumpsLength; 1578 1579 /* check */ 1580 if (srcSize < 5) return ERROR(srcSize_wrong); 1581 1582 /* SeqHead */ 1583 *nbSeq = ZSTD_readLE16(ip); ip+=2; 1584 LLtype = *ip >> 6; 1585 Offtype = (*ip >> 4) & 3; 1586 MLtype = (*ip >> 2) & 3; 1587 if (*ip & 2) 1588 { 1589 dumpsLength = ip[2]; 1590 dumpsLength += ip[1] << 8; 1591 ip += 3; 1592 } 1593 else 1594 { 1595 dumpsLength = ip[1]; 1596 dumpsLength += (ip[0] & 1) << 8; 1597 ip += 2; 1598 } 1599 *dumpsPtr = ip; 1600 ip += dumpsLength; 1601 *dumpsLengthPtr = dumpsLength; 1602 1603 /* check */ 1604 if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */ 1605 1606 /* sequences */ 1607 { 1608 S16 norm[MaxML+1]; /* assumption : MaxML >= MaxLL and MaxOff */ 1609 size_t headerSize; 1610 1611 /* Build DTables */ 1612 switch(LLtype) 1613 { 1614 case bt_rle : 1615 LLlog = 0; 1616 FSE_buildDTable_rle(DTableLL, *ip++); break; 1617 case bt_raw : 1618 LLlog = LLbits; 1619 FSE_buildDTable_raw(DTableLL, LLbits); break; 1620 default : 1621 { U32 max = MaxLL; 1622 headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip); 1623 if (FSE_isError(headerSize)) return ERROR(GENERIC); 1624 if (LLlog > LLFSELog) return ERROR(corruption_detected); 1625 ip += headerSize; 1626 FSE_buildDTable(DTableLL, norm, max, LLlog); 1627 } } 1628 1629 switch(Offtype) 1630 { 1631 case bt_rle : 1632 Offlog = 0; 1633 if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ 1634 FSE_buildDTable_rle(DTableOffb, *ip++); break; 1635 case bt_raw : 1636 Offlog = Offbits; 1637 FSE_buildDTable_raw(DTableOffb, Offbits); break; 1638 default : 1639 { U32 max = MaxOff; 1640 headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip); 1641 if (FSE_isError(headerSize)) return ERROR(GENERIC); 1642 if (Offlog > OffFSELog) return ERROR(corruption_detected); 1643 ip += headerSize; 1644 FSE_buildDTable(DTableOffb, norm, max, Offlog); 1645 } } 1646 1647 switch(MLtype) 1648 { 1649 case bt_rle : 1650 MLlog = 0; 1651 if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */ 1652 FSE_buildDTable_rle(DTableML, *ip++); break; 1653 case bt_raw : 1654 MLlog = MLbits; 1655 FSE_buildDTable_raw(DTableML, MLbits); break; 1656 default : 1657 { U32 max = MaxML; 1658 headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip); 1659 if (FSE_isError(headerSize)) return ERROR(GENERIC); 1660 if (MLlog > MLFSELog) return ERROR(corruption_detected); 1661 ip += headerSize; 1662 FSE_buildDTable(DTableML, norm, max, MLlog); 1663 } } } 1664 1665 return ip-istart; 1666 } 1667 1668 1669 typedef struct { 1670 size_t litLength; 1671 size_t offset; 1672 size_t matchLength; 1673 } seq_t; 1674 1675 typedef struct { 1676 FSE_DStream_t DStream; 1677 FSE_DState_t stateLL; 1678 FSE_DState_t stateOffb; 1679 FSE_DState_t stateML; 1680 size_t prevOffset; 1681 const BYTE* dumps; 1682 const BYTE* dumpsEnd; 1683 } seqState_t; 1684 1685 1686 static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState) 1687 { 1688 size_t litLength; 1689 size_t prevOffset; 1690 size_t offset; 1691 size_t matchLength; 1692 const BYTE* dumps = seqState->dumps; 1693 const BYTE* const de = seqState->dumpsEnd; 1694 1695 /* Literal length */ 1696 litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream)); 1697 prevOffset = litLength ? seq->offset : seqState->prevOffset; 1698 seqState->prevOffset = seq->offset; 1699 if (litLength == MaxLL) 1700 { 1701 const U32 add = dumps<de ? *dumps++ : 0; 1702 if (add < 255) litLength += add; 1703 else 1704 { 1705 if (dumps<=(de-3)) 1706 { 1707 litLength = ZSTD_readLE24(dumps); 1708 dumps += 3; 1709 } 1710 } 1711 } 1712 1713 /* Offset */ 1714 { 1715 U32 offsetCode, nbBits; 1716 offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream)); 1717 if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); 1718 nbBits = offsetCode - 1; 1719 if (offsetCode==0) nbBits = 0; /* cmove */ 1720 offset = ((size_t)1 << (nbBits & ((sizeof(offset)*8)-1))) + FSE_readBits(&(seqState->DStream), nbBits); 1721 if (ZSTD_32bits()) FSE_reloadDStream(&(seqState->DStream)); 1722 if (offsetCode==0) offset = prevOffset; 1723 } 1724 1725 /* MatchLength */ 1726 matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream)); 1727 if (matchLength == MaxML) 1728 { 1729 const U32 add = dumps<de ? *dumps++ : 0; 1730 if (add < 255) matchLength += add; 1731 else 1732 { 1733 if (dumps<=(de-3)) 1734 { 1735 matchLength = ZSTD_readLE24(dumps); 1736 dumps += 3; 1737 } 1738 } 1739 } 1740 matchLength += MINMATCH; 1741 1742 /* save result */ 1743 seq->litLength = litLength; 1744 seq->offset = offset; 1745 seq->matchLength = matchLength; 1746 seqState->dumps = dumps; 1747 } 1748 1749 1750 static size_t ZSTD_execSequence(BYTE* op, 1751 seq_t sequence, 1752 const BYTE** litPtr, const BYTE* const litLimit, 1753 BYTE* const base, BYTE* const oend) 1754 { 1755 static const int dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ 1756 static const int dec64table[] = {8, 8, 8, 7, 8, 9,10,11}; /* subtracted */ 1757 const BYTE* const ostart = op; 1758 const size_t litLength = sequence.litLength; 1759 BYTE* const endMatch = op + litLength + sequence.matchLength; /* risk : address space overflow (32-bits) */ 1760 const BYTE* const litEnd = *litPtr + litLength; 1761 1762 /* check */ 1763 if (endMatch > oend) return ERROR(dstSize_tooSmall); /* overwrite beyond dst buffer */ 1764 if (litEnd > litLimit) return ERROR(corruption_detected); 1765 if (sequence.matchLength > (size_t)(*litPtr-op)) return ERROR(dstSize_tooSmall); /* overwrite literal segment */ 1766 1767 /* copy Literals */ 1768 if (((size_t)(*litPtr - op) < 8) || ((size_t)(oend-litEnd) < 8) || (op+litLength > oend-8)) 1769 memmove(op, *litPtr, litLength); /* overwrite risk */ 1770 else 1771 ZSTD_wildcopy(op, *litPtr, litLength); 1772 op += litLength; 1773 *litPtr = litEnd; /* update for next sequence */ 1774 1775 /* check : last match must be at a minimum distance of 8 from end of dest buffer */ 1776 if (oend-op < 8) return ERROR(dstSize_tooSmall); 1777 1778 /* copy Match */ 1779 { 1780 const U32 overlapRisk = (((size_t)(litEnd - endMatch)) < 12); 1781 const BYTE* match = op - sequence.offset; /* possible underflow at op - offset ? */ 1782 size_t qutt = 12; 1783 U64 saved[2]; 1784 1785 /* check */ 1786 if (match < base) return ERROR(corruption_detected); 1787 if (sequence.offset > (size_t)base) return ERROR(corruption_detected); 1788 1789 /* save beginning of literal sequence, in case of write overlap */ 1790 if (overlapRisk) 1791 { 1792 if ((endMatch + qutt) > oend) qutt = oend-endMatch; 1793 memcpy(saved, endMatch, qutt); 1794 } 1795 1796 if (sequence.offset < 8) 1797 { 1798 const int dec64 = dec64table[sequence.offset]; 1799 op[0] = match[0]; 1800 op[1] = match[1]; 1801 op[2] = match[2]; 1802 op[3] = match[3]; 1803 match += dec32table[sequence.offset]; 1804 ZSTD_copy4(op+4, match); 1805 match -= dec64; 1806 } else { ZSTD_copy8(op, match); } 1807 op += 8; match += 8; 1808 1809 if (endMatch > oend-(16-MINMATCH)) 1810 { 1811 if (op < oend-8) 1812 { 1813 ZSTD_wildcopy(op, match, (oend-8) - op); 1814 match += (oend-8) - op; 1815 op = oend-8; 1816 } 1817 while (op<endMatch) *op++ = *match++; 1818 } 1819 else 1820 ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8); /* works even if matchLength < 8 */ 1821 1822 /* restore, in case of overlap */ 1823 if (overlapRisk) memcpy(endMatch, saved, qutt); 1824 } 1825 1826 return endMatch-ostart; 1827 } 1828 1829 typedef struct ZSTDv01_Dctx_s 1830 { 1831 U32 LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; 1832 U32 OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; 1833 U32 MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; 1834 void* previousDstEnd; 1835 void* base; 1836 size_t expected; 1837 blockType_t bType; 1838 U32 phase; 1839 } dctx_t; 1840 1841 1842 static size_t ZSTD_decompressSequences( 1843 void* ctx, 1844 void* dst, size_t maxDstSize, 1845 const void* seqStart, size_t seqSize, 1846 const BYTE* litStart, size_t litSize) 1847 { 1848 dctx_t* dctx = (dctx_t*)ctx; 1849 const BYTE* ip = (const BYTE*)seqStart; 1850 const BYTE* const iend = ip + seqSize; 1851 BYTE* const ostart = (BYTE* const)dst; 1852 BYTE* op = ostart; 1853 BYTE* const oend = ostart + maxDstSize; 1854 size_t errorCode, dumpsLength; 1855 const BYTE* litPtr = litStart; 1856 const BYTE* const litEnd = litStart + litSize; 1857 int nbSeq; 1858 const BYTE* dumps; 1859 U32* DTableLL = dctx->LLTable; 1860 U32* DTableML = dctx->MLTable; 1861 U32* DTableOffb = dctx->OffTable; 1862 BYTE* const base = (BYTE*) (dctx->base); 1863 1864 /* Build Decoding Tables */ 1865 errorCode = ZSTDv01_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength, 1866 DTableLL, DTableML, DTableOffb, 1867 ip, iend-ip); 1868 if (ZSTDv01_isError(errorCode)) return errorCode; 1869 ip += errorCode; 1870 1871 /* Regen sequences */ 1872 { 1873 seq_t sequence; 1874 seqState_t seqState; 1875 1876 memset(&sequence, 0, sizeof(sequence)); 1877 seqState.dumps = dumps; 1878 seqState.dumpsEnd = dumps + dumpsLength; 1879 seqState.prevOffset = 1; 1880 errorCode = FSE_initDStream(&(seqState.DStream), ip, iend-ip); 1881 if (FSE_isError(errorCode)) return ERROR(corruption_detected); 1882 FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL); 1883 FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb); 1884 FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML); 1885 1886 for ( ; (FSE_reloadDStream(&(seqState.DStream)) <= FSE_DStream_completed) && (nbSeq>0) ; ) 1887 { 1888 size_t oneSeqSize; 1889 nbSeq--; 1890 ZSTD_decodeSequence(&sequence, &seqState); 1891 oneSeqSize = ZSTD_execSequence(op, sequence, &litPtr, litEnd, base, oend); 1892 if (ZSTDv01_isError(oneSeqSize)) return oneSeqSize; 1893 op += oneSeqSize; 1894 } 1895 1896 /* check if reached exact end */ 1897 if ( !FSE_endOfDStream(&(seqState.DStream)) ) return ERROR(corruption_detected); /* requested too much : data is corrupted */ 1898 if (nbSeq<0) return ERROR(corruption_detected); /* requested too many sequences : data is corrupted */ 1899 1900 /* last literal segment */ 1901 { 1902 size_t lastLLSize = litEnd - litPtr; 1903 if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall); 1904 if (op != litPtr) memmove(op, litPtr, lastLLSize); 1905 op += lastLLSize; 1906 } 1907 } 1908 1909 return op-ostart; 1910 } 1911 1912 1913 static size_t ZSTD_decompressBlock( 1914 void* ctx, 1915 void* dst, size_t maxDstSize, 1916 const void* src, size_t srcSize) 1917 { 1918 /* blockType == blockCompressed, srcSize is trusted */ 1919 const BYTE* ip = (const BYTE*)src; 1920 const BYTE* litPtr = NULL; 1921 size_t litSize = 0; 1922 size_t errorCode; 1923 1924 /* Decode literals sub-block */ 1925 errorCode = ZSTDv01_decodeLiteralsBlock(ctx, dst, maxDstSize, &litPtr, &litSize, src, srcSize); 1926 if (ZSTDv01_isError(errorCode)) return errorCode; 1927 ip += errorCode; 1928 srcSize -= errorCode; 1929 1930 return ZSTD_decompressSequences(ctx, dst, maxDstSize, ip, srcSize, litPtr, litSize); 1931 } 1932 1933 1934 size_t ZSTDv01_decompressDCtx(void* ctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) 1935 { 1936 const BYTE* ip = (const BYTE*)src; 1937 const BYTE* iend = ip + srcSize; 1938 BYTE* const ostart = (BYTE* const)dst; 1939 BYTE* op = ostart; 1940 BYTE* const oend = ostart + maxDstSize; 1941 size_t remainingSize = srcSize; 1942 U32 magicNumber; 1943 size_t errorCode=0; 1944 blockProperties_t blockProperties; 1945 1946 /* Frame Header */ 1947 if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong); 1948 magicNumber = ZSTD_readBE32(src); 1949 if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); 1950 ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; 1951 1952 /* Loop on each block */ 1953 while (1) 1954 { 1955 size_t blockSize = ZSTDv01_getcBlockSize(ip, iend-ip, &blockProperties); 1956 if (ZSTDv01_isError(blockSize)) return blockSize; 1957 1958 ip += ZSTD_blockHeaderSize; 1959 remainingSize -= ZSTD_blockHeaderSize; 1960 if (blockSize > remainingSize) return ERROR(srcSize_wrong); 1961 1962 switch(blockProperties.blockType) 1963 { 1964 case bt_compressed: 1965 errorCode = ZSTD_decompressBlock(ctx, op, oend-op, ip, blockSize); 1966 break; 1967 case bt_raw : 1968 errorCode = ZSTD_copyUncompressedBlock(op, oend-op, ip, blockSize); 1969 break; 1970 case bt_rle : 1971 return ERROR(GENERIC); /* not yet supported */ 1972 break; 1973 case bt_end : 1974 /* end of frame */ 1975 if (remainingSize) return ERROR(srcSize_wrong); 1976 break; 1977 default: 1978 return ERROR(GENERIC); 1979 } 1980 if (blockSize == 0) break; /* bt_end */ 1981 1982 if (ZSTDv01_isError(errorCode)) return errorCode; 1983 op += errorCode; 1984 ip += blockSize; 1985 remainingSize -= blockSize; 1986 } 1987 1988 return op-ostart; 1989 } 1990 1991 size_t ZSTDv01_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize) 1992 { 1993 dctx_t ctx; 1994 ctx.base = dst; 1995 return ZSTDv01_decompressDCtx(&ctx, dst, maxDstSize, src, srcSize); 1996 } 1997 1998 /* ZSTD_errorFrameSizeInfoLegacy() : 1999 assumes `cSize` and `dBound` are _not_ NULL */ 2000 static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret) 2001 { 2002 *cSize = ret; 2003 *dBound = ZSTD_CONTENTSIZE_ERROR; 2004 } 2005 2006 void ZSTDv01_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound) 2007 { 2008 const BYTE* ip = (const BYTE*)src; 2009 size_t remainingSize = srcSize; 2010 size_t nbBlocks = 0; 2011 U32 magicNumber; 2012 blockProperties_t blockProperties; 2013 2014 /* Frame Header */ 2015 if (srcSize < ZSTD_frameHeaderSize+ZSTD_blockHeaderSize) { 2016 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); 2017 return; 2018 } 2019 magicNumber = ZSTD_readBE32(src); 2020 if (magicNumber != ZSTD_magicNumber) { 2021 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown)); 2022 return; 2023 } 2024 ip += ZSTD_frameHeaderSize; remainingSize -= ZSTD_frameHeaderSize; 2025 2026 /* Loop on each block */ 2027 while (1) 2028 { 2029 size_t blockSize = ZSTDv01_getcBlockSize(ip, remainingSize, &blockProperties); 2030 if (ZSTDv01_isError(blockSize)) { 2031 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, blockSize); 2032 return; 2033 } 2034 2035 ip += ZSTD_blockHeaderSize; 2036 remainingSize -= ZSTD_blockHeaderSize; 2037 if (blockSize > remainingSize) { 2038 ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong)); 2039 return; 2040 } 2041 2042 if (blockSize == 0) break; /* bt_end */ 2043 2044 ip += blockSize; 2045 remainingSize -= blockSize; 2046 nbBlocks++; 2047 } 2048 2049 *cSize = ip - (const BYTE*)src; 2050 *dBound = nbBlocks * BLOCKSIZE; 2051 } 2052 2053 /******************************* 2054 * Streaming Decompression API 2055 *******************************/ 2056 2057 size_t ZSTDv01_resetDCtx(ZSTDv01_Dctx* dctx) 2058 { 2059 dctx->expected = ZSTD_frameHeaderSize; 2060 dctx->phase = 0; 2061 dctx->previousDstEnd = NULL; 2062 dctx->base = NULL; 2063 return 0; 2064 } 2065 2066 ZSTDv01_Dctx* ZSTDv01_createDCtx(void) 2067 { 2068 ZSTDv01_Dctx* dctx = (ZSTDv01_Dctx*)malloc(sizeof(ZSTDv01_Dctx)); 2069 if (dctx==NULL) return NULL; 2070 ZSTDv01_resetDCtx(dctx); 2071 return dctx; 2072 } 2073 2074 size_t ZSTDv01_freeDCtx(ZSTDv01_Dctx* dctx) 2075 { 2076 free(dctx); 2077 return 0; 2078 } 2079 2080 size_t ZSTDv01_nextSrcSizeToDecompress(ZSTDv01_Dctx* dctx) 2081 { 2082 return ((dctx_t*)dctx)->expected; 2083 } 2084 2085 size_t ZSTDv01_decompressContinue(ZSTDv01_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize) 2086 { 2087 dctx_t* ctx = (dctx_t*)dctx; 2088 2089 /* Sanity check */ 2090 if (srcSize != ctx->expected) return ERROR(srcSize_wrong); 2091 if (dst != ctx->previousDstEnd) /* not contiguous */ 2092 ctx->base = dst; 2093 2094 /* Decompress : frame header */ 2095 if (ctx->phase == 0) 2096 { 2097 /* Check frame magic header */ 2098 U32 magicNumber = ZSTD_readBE32(src); 2099 if (magicNumber != ZSTD_magicNumber) return ERROR(prefix_unknown); 2100 ctx->phase = 1; 2101 ctx->expected = ZSTD_blockHeaderSize; 2102 return 0; 2103 } 2104 2105 /* Decompress : block header */ 2106 if (ctx->phase == 1) 2107 { 2108 blockProperties_t bp; 2109 size_t blockSize = ZSTDv01_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); 2110 if (ZSTDv01_isError(blockSize)) return blockSize; 2111 if (bp.blockType == bt_end) 2112 { 2113 ctx->expected = 0; 2114 ctx->phase = 0; 2115 } 2116 else 2117 { 2118 ctx->expected = blockSize; 2119 ctx->bType = bp.blockType; 2120 ctx->phase = 2; 2121 } 2122 2123 return 0; 2124 } 2125 2126 /* Decompress : block content */ 2127 { 2128 size_t rSize; 2129 switch(ctx->bType) 2130 { 2131 case bt_compressed: 2132 rSize = ZSTD_decompressBlock(ctx, dst, maxDstSize, src, srcSize); 2133 break; 2134 case bt_raw : 2135 rSize = ZSTD_copyUncompressedBlock(dst, maxDstSize, src, srcSize); 2136 break; 2137 case bt_rle : 2138 return ERROR(GENERIC); /* not yet handled */ 2139 break; 2140 case bt_end : /* should never happen (filtered at phase 1) */ 2141 rSize = 0; 2142 break; 2143 default: 2144 return ERROR(GENERIC); 2145 } 2146 ctx->phase = 1; 2147 ctx->expected = ZSTD_blockHeaderSize; 2148 ctx->previousDstEnd = (void*)( ((char*)dst) + rSize); 2149 return rSize; 2150 } 2151 2152 } 2153